Printed circuit board

Abstract

A printed circuit board includes an insulating layer and a wiring pattern disposed on or within the insulating layer, wherein the wiring pattern includes a first metal layer, a second metal layer disposed on an upper surface of the first metal layer, and an inorganic oxide film disposed on a side surface of the second metal layer.

What is claimed is: 
     
         1 . A printed circuit board comprising:
 an insulating layer; and   a wiring pattern disposed on or within the insulating layer,   wherein the wiring pattern includes a first metal layer, a second metal layer disposed on an upper surface of the first metal layer, and an inorganic oxide film disposed on a side surface of the second metal layer.   
     
     
         2 . The printed circuit board of  claim 1 , wherein
 the second metal layer is thicker than the first metal layer, and   the first metal layer is thicker than the inorganic oxide layer.   
     
     
         3 . The printed circuit board of  claim 1 , wherein the inorganic oxide film has a thickness less than 100 nm. 
     
     
         4 . The printed circuit board of  claim 1 , wherein the inorganic oxide film includes at least one of Al 2 O 3 , TiO 2 , ZnO, ZnO 2 , ZrO 2 , SnO, SnO 2 , HfO 2 , or SiO 2 . 
     
     
         5 . The printed circuit board of  claim 1 , wherein at least a portion of a side surface of the first metal layer is exposed from the inorganic oxide film. 
     
     
         6 . The printed circuit board of  claim 5 , wherein
 the inorganic oxide film is spaced apart from a portion of the side surface of the first metal layer, and   the inorganic oxide film is spaced apart from a portion of the upper surface of the second metal layer.   
     
     
         7 . The printed circuit board of  claim 6 , wherein
 the inorganic oxide film does not cover the side surface of the first metal layer, and   the inorganic oxide film does not cover the upper surface of the second metal layer.   
     
     
         8 . The printed circuit board of  claim 1 , wherein
 a side surface of the first metal layer protrudes compared to the side surface of the second metal layer, and   the inorganic oxide film is disposed to extend onto a protruding region of the first metal layer.   
     
     
         9 . The printed circuit board of  claim 1 , wherein
 the inorganic oxide film disposed on the side surface of the second metal layer is bent to be disposed on a portion of an upper surface of the first metal layer at the protruding region.   
     
     
         10 . The printed circuit board of  claim 1 , wherein the first and second metal layers have different average grain sizes. 
     
     
         11 . The printed circuit board of  claim 10 , wherein
 the first metal layer includes chemical copper, and   the second metal layer includes electrolytic copper.   
     
     
         12 . The printed circuit board of  claim 1 , wherein
 the wiring pattern is provided in plural, and   the plurality of wiring patterns have a line L/space S less than 10 μm/10 μm.   
     
     
         13 . The printed circuit board of  claim 1 , wherein
 the insulating layer includes first and second insulating layers,   the wiring pattern is disposed on an upper surface of the first insulating layer,   the second insulating layer is disposed on an upper surface of the first insulating layer, and   the second insulating layer covers at least a portion of the wiring pattern.   
     
     
         14 . A printed circuit board comprising:
 a substrate;   a first metal layer disposed on the substrate;   a second metal layer disposed on the first metal layer; and   a barrier layer disposed to surround the second metal layer and having a protrusion at least partially protruding from a lower end of the barrier layer in a plane direction, perpendicular to a stacking direction.   
     
     
         15 . The printed circuit board of  claim 14 , wherein
 the first metal layer is wider than the second metal layer on a cross-section of the plane direction and the stacking direction, and   the protrusion covers a portion of an upper surface of the first metal layer and is spaced apart from a portion of a side surface of the first metal layer.   
     
     
         16 . The printed circuit board of  claim 14 , wherein
 the second metal layer is thicker than the first metal layer, and   the first metal layer is thicker than the barrier layer.   
     
     
         17 . The printed circuit board of  claim 14 , wherein the barrier layer includes an inorganic oxide film having a thickness less than 100 nm. 
     
     
         18 . The printed circuit board of  claim 17 , wherein the inorganic oxide film includes at least one of Al 2 O 3 , TiO 2 , ZnO, ZnO 2 , ZrO 2 , SnO, SnO 2 , HfO 2 , or SiO 2 .